Device and method for communicating teletype information in a vehicle communication system

ABSTRACT

A communication system and method for transmitting and receiving teletype information in a vehicle ( 20 ). The communication system ( 22 ) includes an external interface ( 24 ) and a communication control unit ( 26 ). The external interface ( 24 ), embedded in the vehicle ( 20 ), is capable of receiving a first set of teletype signals from a portable TTY terminal ( 50 ) and capable of sending a second set of teletype signal to the portable TTY terminal ( 50 ). The communication control unit ( 26 ), also embedded in the vehicle ( 20 ), is connected to the external interface ( 24 ) and comprises a controller ( 36 ) and a transceiver ( 34 ). The transceiver ( 34 ) is capable of transmitting messages over a wireless communication link (A) that contain information from the first set of teletype signals. The transceiver ( 34 ) is also capable of receiving messages over the wireless communication link (A) that contain information for the second set of teletype signals.

FIELD OF THE INVENTION

[0001] This invention in general relates to wireless communicationsystems in a vehicle and, more particularly, to a device and method in avehicle that is capable of transmitting and receiving teletypeinformation for physically impaired persons.

BACKGROUND OF THE INVENTION

[0002] Individuals who are deaf, sound impaired, and/or speech impairedare able to communicate over a telephone network through aTelecommunication Device for the Deaf (TDD) such as a textteletypewriter (TTY) terminal. To communicate, a person types his or herconversation on a keypad of a terminal. Each letter is transmitted by anelectronic code called Baudot. Baudot code is a 45.45 bps binaryfrequency shift keyed scheme that is half duplex, and without errorprotection. Each bit has a nominal duration of 22 ms and a characterconsists of 1 start bit, 5 data bits, and 2 stop bits. A mark, or “1”,is transmitted with a 1400 Hz tone. The space, or “0”, is transmittedwith an 1800 Hz tone. The electronic code is sent from the transmittingTTY terminal to a receiving TTY terminal over telephone lines in theform of tones. The receiving TTY terminal transforms the tones back toletters on a display screen. The conversation typed by the person at thetransmitting TTY terminal may then be read on the display screen of thereceiving TTY terminal.

[0003] A person can also use a computer with a TTY modem to communicatewith someone who has a TTY terminal. Computers generally operate inAmerican Standard Code for Information Interexchange (ASCII). Tocommunicate with a TTY terminal, a person who uses ASCII must use anASCII/Baudot modem and related software to convert the ASCII code intoBaudot code.

[0004] Wireless service providers currently support the transmittal ofTTY information for emergency (911) calls. This may be done through ahandheld mobile cellular phone. A need currently exist, however, forproviding a system and method that can handle teletype information andthat can be easily integrated into vehicular communication systems, suchas an embedded in-vehicle Telematics system. This would provide asignificant benefit to physically impaired individuals who desire to usea portable TTY terminal in a vehicle.

[0005] It is, therefore, desirable to provide an improved wirelesscommunications in vehicles and method to overcome or minimize most, ifnot all, of the preceding problems especially in the area ofcommunications for physically impaired individuals.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006]FIG. 1 is a perspective view of a communication system in avehicle having the capability of transmitting and receiving teletypeinformation according to one embodiment of the present invention;

[0007]FIG. 2 is a perspective view of one embodiment of a connector thatmay be used in the system shown in FIG. 1;

[0008]FIG. 3 is a block diagram of one embodiment of the system shown inFIG. 1;

[0009]FIG. 4 is a block diagram of another embodiment of the systemshown in FIG. 1;

[0010]FIG. 5 is a block diagram of a further embodiment of the systemshown in FIG. 1;

[0011]FIG. 6 is a flow diagram of a method for establishing a wirelesscommunication link between a vehicle and a remote station;

[0012]FIGS. 6-10 are flow diagrams of a method for communicatingteletype information in a vehicle communication system;

[0013]FIG. 11 is a perspective view of another embodiment of acommunication system in a vehicle having the capability of transmittingand receiving teletype information;

[0014]FIG. 12 is a block diagram of one embodiment of the system shownin FIG. 11;

[0015]FIG. 13 is a perspective view of further embodiment of acommunication system in a vehicle having the capability of transmittingand receiving teletype information;

[0016]FIG. 14 is a block diagram of one embodiment of the system shownin FIG. 13;

[0017]FIG. 15 is a perspective view of yet another embodiment of acommunication system in a vehicle having the capability of transmittingand receiving teletype information; and

[0018]FIG. 16 is a block diagram of one embodiment of the system shownin FIG. 15.

[0019] While the invention is susceptible to various modifications andalternative forms, specific embodiments have been shown by way ofexample in the drawings and will be described in detail herein. However,it should be understood that the invention is not intended to be limitedto the particular forms disclosed. Rather, the invention is to cover allmodifications, equivalents and alternatives falling within the spiritand scope of the invention as defined by the appended claims.

DETAILED DESCRIPTION

[0020] What is described is a system and method for transmitting andreceiving teletype information in a vehicle. To this end, in oneembodiment there is a communication system in a vehicle. The vehicularcommunication system includes an external interface and a communicationcontrol unit. The external interface, embedded in the vehicle, iscapable of receiving a first set of teletype signals from a portable TTYterminal and capable of sending a second set of teletype signal to theportable TTY terminal. The communication control unit, also embedded inthe vehicle, is connected to the external interface and comprises acontroller and a transceiver. The transceiver is capable of transmittingmessages over a wireless communication link that contain informationfrom the first set of teletype signals. The transceiver is also capableof receiving messages over the wireless communication link that containinformation for the second set of teletype signals.

[0021] In another embodiment, there is a communication system for avehicle that comprises a communication control unit, an externalinterface, a removable communication cord, and a portable TTY terminal.The communication control unit and the external interface are embeddedin the vehicle and connected to each other. The removable communicationcord is connected between the external interface and the portable TTYterminal. The portable TTY terminal has at least a keypad and a displayand is capable of sending a first set of teletype signals and capable ofreceiving a second set of teletype signals. These teletype signals arecommunicated to and from the communication control unit over theremovable communication cord. Accordingly, the communication controlunit is capable of receiving the first set of teletype signals from theportable TTY terminal and is capable of sending the second set ofteletype signals to the portable TTY terminal.

[0022] In one embodiment, the removable communication cord includes afirst audio wire, a second audio wire, and a ground wire. In anotherembodiment, the communication cord may further include a control wireand/or a power wire. An operational mode switch may be embedded in theportable TTY terminal or in the vehicle to provide the operator with theoption to select a set of operational modes such as a normal teletypemode, a voice carry over mode, and a hearing carry over mode. In thenormal teletype mode, the user may provide information for the first setof teletype signals through the keypad of the portable TTY terminal. Theuser may also receive information from the second set of teletypesignals through the display of the portable TTY terminal. In the voicecarry over mode, any audio information for a conversation may beprovided by the user through a microphone in the portable TTY terminalor through a microphone embedded in the vehicle. In the hearing carryover mode, the user may hear any audio information for a conversationthough a speaker in the portable TTY terminal or through a speakerembedded in the vehicle.

[0023] There is also a method for establishing a wireless communicationlink between a vehicle and a remote station that comprises the steps of:determining, by the vehicle, whether an occupant of a vehicle desires toestablish a wireless communication link with a remote station;establishing, by the vehicle, the wireless communication link betweenthe vehicle and the remote station after it is determined that anoccupant desires to establish the wireless communication link;transmitting, by the remote station, a first message to the occupant ofthe vehicle, the first message including a voice communication; waiting,by the remote station, for a response message from the occupant of thevehicle during a first period of time, the response message including avoice communication; and if no response message is received from theoccupant of the vehicle during the first period of time, transmitting,by the remote station, a second message to the occupant of the vehicle,the second message including teletype information. The method may alsocomprise the steps of: receiving, by the vehicle, the second message tothe occupant of the vehicle; converting, by the vehicle, the teletypeinformation in the second message to a set of teletype signals; andtransmitting, by the vehicle, the set of teletype signals to a portableTTY terminal. The method may further comprise the step of: waiting, bythe remote station, for a teletype response message from the occupant ofthe vehicle during a second period of time, the teletype responsemessage including teletype information.

[0024] Another embodiment includes a method in a vehicle communicationsystem for establishing a wireless communication link between thevehicle communication system and a remote station. The method comprisesthe steps of: sending a user prompt from the vehicle communicationsystem to a portable TTY terminal; determining at the vehiclecommunication system whether a user input is received from the portableTTY terminal; if a user input is received from the portable TTYterminal, determining whether the user input includes a dial command; ifthe user input includes a dial command, establishing the wirelesscommunication link between the vehicle communication system and theremote station. The method may further comprise the steps of:determining whether the dial command includes a telephone number; and ifthe dial command includes a telephone number, establishing the wirelesscommunication link between the vehicle communication system and theremote station based on the telephone number included in the dialcommand.

[0025] There are also methods that include steps such as: determining atthe vehicle communication system whether an incoming data messageexists, determining at the vehicle communication system whether anincoming call exists, and determining at the communication systemwhether a vehicle alert exits. Based on those determinations, thevehicle communication system may communicate with the portable TTYterminal in a variety of ways.

[0026] Now, turning to the drawings, FIG. 1 is a perspective view of thecabin of a vehicle 20 having a communication system 22. In oneembodiment, the communication system 22 may include an externalinterface 24, a communication control unit 26, an antenna 28, amicrophone 30, and a speaker 32. The communication control unit 26 isembedded in the vehicle 20 and may be generally directed to providingTelematics services to an occupant of the vehicle 20.

[0027] The communication control unit 26 is connected to the antenna 28in order to provide wireless communications over a wirelesscommunication link A with a remote station (not shown). The remotestation may be a Telematics related service center or other remotedevice. The communication control unit 26 may have a transceiver that iscapable of establishing and accepting voice calls through the antenna 28and over the wireless communication link A. For instance, thetransceiver in the communication control unit 26 may be a cellulartransceiver and operate according to an analog wireless communicationprotocol such as the Advanced Mobile Phone System (AMPS) or operateaccording to a digital wireless communication protocol such as a CodeDivision Multiple Access (CDMA) protocol, a Time Division MultipleAccess (TDMA) protocol, or the Global System for Mobile Communications(GSM) protocol. Moreover, the transceiver may operate according to oneof several types of bearer services to transmit data between thecommunication control unit 26 and the remote station such as generalpacket radio service (GPRS), short message service (SMS), circuitswitched data service (CSD), or high-speed circuit switched data service(HSCSD).

[0028] The present invention is directed to an improved communicationsystem in a vehicle that is further capable of transmitting andreceiving teletype information for physically impaired individuals.Accordingly, the communication system 22 of the present inventionincludes an external interface 24 that is embedded in the vehicle 20. Aswill be explained in more detail below, the main purpose of the externalinterface 24 will be to receive a first set of teletype signals from aportable TTY terminal 50 and to send a second set of teletype signals tothe portable TTY terminal 50. In one embodiment, the external interface24 is a wired connection as shown in FIGS. 1-5, 11-14. In anotherembodiment, the external interface 24 is a wireless connection as shownin FIGS. 15 and 16. In a further embodiment, the external interface 24includes the vehicle microphone 30 and vehicle speakers 32. In thatcase, the teletype signals are transferred over the air to the portableTTY terminal 50 through sound waves.

[0029] Referring to FIGS. 1-5, in one embodiment, a first set ofteletype signals and a second set of teletype signals are transferredbetween the communication system 22 and the portable TTY terminal 50 viaa removable communication cord 40 having end connectors 42. FIG. 2 showsone embodiment of a suitable end connector 42 similar to a 2.5 mm jackconnector. In this embodiment, the connector 42 may have threeelectrical contacts 44, 46, 48. The electrical contacts 44, 46, 48 areconnected to wires 45, 47, 49 (see FIGS. 3, 4) in the removablecommunication cord 40.

[0030] The first electrical contact 44 may be located at the tip of theconnector 42 and may provide for the transfer of the first set ofteletype signals from the portable TTY terminal 50 to the vehiclecommunication system 22 via the wire 45 in the communication cord 40.The vehicle communication system 22 receives the teletype signals andgenerates messages over the wireless communication link A that containthe Baudot tones or other information representative of the tones.

[0031] The second electrical contact 46 may be located in the middle ofthe connector 42 and may provide for the transfer of the second set ofteletype signals from the communication system 22 to the portable TTYterminal 50 via the wire 47 in the communication cord 40. The portableTTY terminal 50 may then extract the information contained in the secondset of teletype signals and generate text for output to the user ondisplay 52.

[0032] The third electrical contact 48 may be located at an innerlocation of the connector 42, opposite the tip, and may provide a groundconnection for the portable TTY terminal 50 via the wire 49 in thecommunication cord 40.

[0033] As will be illustrated in more detail below, the differencebetween FIG. 3 and FIG. 4 is that the vehicle communication system 22shown in FIG. 4 includes a modem 37. The addition of a modem 37 to thevehicle communication system 22 enables a vehicle controller 36 toreceive and transmit control information with a controller 55 in theportable TTY terminal 50. This may be important in some applicationswhere a desire exists to allow the controller 55 in the portable TTYterminal 50 to inform the vehicle controller 36 of a particular mode ofoperation, as will be explained in more detail below. Anotherapplication may include allowing the controller 55 in the portable TTYterminal 50 to inform the vehicle controller 36 when to establish awireless communication link A. A further application may includeallowing the controller 55 in the portable TTY terminal 50 to inform thevehicle controller 36 of a particular telephone number to use whenattempting to establish a wireless communication link A.

[0034] In another embodiment of the present invention, referring to FIG.5, the connector 42 may further include other electrical contacts orpins for control and/or power. For instance, the communication cord 40may have an additional wire 43 for a serial connection for the transferof control signals between the controller 55 in the portable TTYterminal 50 and the controller 36 in the vehicle communication system22. As mentioned previously, this may be beneficial in applicationswhere the controller 55 in the portable TTY terminal 50 would like toinform the vehicle controller 36 of a particular mode of operation, whento establish the wireless communication link A, or specific informationregarding how to establish the wireless communication link A.

[0035] The present invention advantageously allows a user of a portableTTY terminal 50, also known as a Telecommunication Device for the Deaf(TDD), to transmit and receive teletype signals through a communicationsystem 22 in a vehicle 20. As will be explained in more detail below, inone embodiment, the portable TTY terminal 50 may include a modem 51, adisplay 52, a keypad 54, a controller 55, a speaker 56, a microphone 58,and an external interface 57. The portable TTY terminal 50 may furtherhave an internal power supply 59 (such as a battery) and/or a connectorfor receiving power from the vehicle 20 through a power cord 60. Theportable TTY terminal 50 may also have a mode selector switch 64 that isconfigured to allow a user to operate the portable TTY terminal 50 inthree modes: a normal TTY mode, a Voice Carry Over (VCO) mode, and aHearing Carry Over (HCO) mode.

[0036] In one embodiment, where the communication cord 40 allows for thecommunication of analog signals, the operation of the portable TTYterminal 50 in the normal TTY mode would allow a user to provide textfor a conversation through the keypad 54 of the portable TTY terminal50. The text entered into the keypad 54 may then be converted into a setof teletype signals by the modem 51 and then transferred to interface 57for communication to the vehicle communication system 22 over the wire45 in the communication cord 40. The normal TTY mode would also allow auser to read text of the conversation through the visual display 52 ofthe portable TTY terminal 50. The text shown on the visual display 52may come from the modem 51 after the interface 57 of the portable TTYterminal 50 receives a set of teletype signals over the wire 47 in thecommunication cord 40.

[0037] The VCO mode may be a communication hybrid of TTY and voice. Inparticular, the operation of the portable TTY terminal 50 in VCO modewould allow a healing impaired user to provide audio information throughthe audio input or microphone 58 of the portable TTY terminal 50. Theaudio information would be transmitted from the portable TTY terminal 50to the vehicle communication system 22 over the wire 45 in thecommunication cord 40. The controller 55 can do this by connecting theexternal interface 57 to the terminal's microphone 58. Alternatively, inembodiments where the communication cord 40 allows the transmission ofcontrol information, the VCO mode may allow a user to provide audioinformation to the transceiver 34 through the microphone 30 embedded inthe vehicle 20. The controller 55 can do this by sending a controlsignal to the controller 36 in the vehicle communication system 22 sothat the input to the transceiver 34 is the vehicle's embeddedmicrophone 30. The VCO mode may also allow a user to read text of theconversation through the visual display 52 of the portable TTY terminal50. The text shown on the visual display 52 may come from the modem 51after the interface 57 of the portable TTY terminal 50 receives the setof teletype signals over the wire 47 in the communication cord 40.Individuals who can speak clearly but have a difficult time hearing mayprefer the VCO mode.

[0038] The HCO mode allows a speaking impaired user to type their wordson the keypad 54 of the TTY terminal 50 but allow the person to hear thecall takers spoken response through an audio output or speaker. Inparticular, the hearing carry over mode may allow a user to provide textfor a conversation through the keypad 54 of the portable TTY terminal50. The text entered into the keypad 54 may then be converted into a setof teletype signals by the modem 51 and then transferred to interface 57for communication to the vehicle communication system 22 over the wire45 in the communication cord 40. The HCO mode would also allow a user toreceive audio information through the speaker 56 of the portable TTYterminal 50. The audio information would be transmitted to the portableTTY terminal 50 from the vehicle communication system 22 over the wire47 in the communication cord 40. The controller 55 can do this byconnecting the output from the external interface 57 to the terminal'sspeaker 56. Alternatively, in embodiments where the communication cord40 allows the transmission of control information, the HCO mode mayallow a user to receive audio information through the speakers 32embedded in the vehicle 20. The controller 55 can do this by sending acontrol signal to the controller 36 in the vehicle communication system22 so that the output from the transceiver 34 is directed to thevehicle's embedded speakers 32. Individuals with speech impairments whoare not deaf or hard of hearing may prefer the HCO mode.

[0039] With respect to the embodiment in FIG. 1, the interaction betweenthe vehicle and a remote station will now be further explained in thecontext of the system diagrams in FIGS. 3-5 and the flow diagram in FIG.6. FIGS. 3-4 illustrate a portable TTY terminal 50 that communicateswith a vehicle communication system 22 through a removable communicationcord 40 having a first wire 45, a second wire 47, and a ground wire 49.FIG. 5 illustrates a portable TTY terminal 50 that communicates with avehicle communication system 22 through a removable communication cord40 having at least a first wire 45, a second wire 47, a ground wire 49,a control wire 43, and a power wire 41.

[0040] Initially, in decision block 102, the vehicle controller 36 maydetermine whether an occupant of the vehicle 20 desires to establish awireless communication link A with a remote station. In one embodiment,the vehicle controller 36 makes this determination by monitoring callbuttons 27 a, 27 b. In particular, a user of the portable TTY terminal50 that desires to establish a wireless communication link A with aremote station may begin a conversation by selecting the call buttons 27a, 27 b on a user interface 25 in the vehicle 20. The call buttons 27 a,27 b may be part of a Telematics application that initiates an emergencycall (E-Call) or an information call (I-Call) via a wirelesscommunication link A. The vehicle controller 36 may also make thisdetermination through a voice recognition system or other user inputmeans in the vehicle 20.

[0041] The vehicle controller 36 may also make the determination indecision block 102 from control information received from the portableTTY terminal 50. This would apply to the embodiments illustrated inFIGS. 4-5, and described in more detail below with respect to FIGS.7-10. In particular, a user of the portable TTY terminal 50 may begin aconversation by selecting a predetermined set of keys on the keypad 54of the TTY terminal 50. The controller 55 in the portable TTY terminal50 would recognize the predetermined set of keys and then send controlinformation to the vehicle's controller 36 to establish a wirelesscommunication link A. In one embodiment, referring to FIG. 4, theportable TTY terminal 50 could transmit the control information in theform of Baudot tones from its internal modem 51 over wire 45 in thecommunication cord 40 to the vehicle modem 37. The vehicle modem 37would then convert the tones to a format type capable of being read andunderstood by the vehicle controller 36. In another embodiment,referring to FIG. 5, the portable TTY terminal 50 could transmit thecontrol information in the form of control signals over control wire 43in the communication cord 40.

[0042] Referring to process block 104, after it is determined that theoccupant of a vehicle 20 would like to establish a wirelesscommunication link A, then the vehicle controller 36 will establish thewireless communication link A with the remote station. This may beaccomplished through the use of a transceiver 34 that is capable ofestablishing wireless links with the remote station using an analog ordigital wireless communication protocol.

[0043] In process block 106, the service center is notified that thevehicle 20 has established a wireless communication link A and isrequesting a response from the service center.

[0044] In process block 108, an operator at a service center may respondby transmitting a first message to the vehicle 20. The first messagewould include a voice communication under a normal Telematicsapplication. The process proceeds to decision block 110 where theservice center will wait for a time period while determining whether aresponse has been received from the vehicle 20 to the first message. Inprocess block 112, if the service center receives a response to thefirst message, then the service center may proceed with thecommunication as a voice call and provide the operator of the vehicle 20with the requested Telematics services. If there is no response to thefirst message, however, then the process may proceed to block 114.

[0045] At process block 114, the service center may then attempt toquery the vehicle 20 by sending a second message that contains teletype(TTY) information to the vehicle 20. In one embodiment, the Baudot tonesare transmitted directly to the vehicle 20 via messages in a voice call.It is noted, however, that the transmittal and receipt of Baudot tonesthrough present digital mobile systems may result in distorted tones.The Telecommunication Industry Association (TIA) has coordinated effortsto find solutions to improve the signaling over wireless communicationlinks. For instance, the TIA has generated an interim standard entitled“TTY/TDD Extension to TIA/EIA 136-410 Enhanced Full Rate Speech Codec,”TIA/EIA/IS-823, May 2000. That standard provides details on extendingthe current Vocoder standard to transport TTY/TDD 45.45 bps and 50 bpsBaudot code. Accordingly, in a second embodiment, the transmission ofthe messages containing teletype information over wireless communicationlink A is done according to this standard.

[0046] When receiving messages, the vehicle transceiver 34 and/or thevehicle controller 36 may be configured to detect the presence ofteletype information. If teletype information is detected in themessage, in one embodiment where the tones are simulated in digitalmessages, a decoder in the transceiver 34 may be used to receive themessages and regenerate the Baudot tones corresponding to the charactersat the specified rates. The Baudot tones for the message would then besent via a set of teletype signals through the vehicle's externalinterface 24, over the wire 47 in the communication cord 40, to theportable TTY terminal 50. The modem 51 in the portable TTY terminal 50would then receive the incoming set of teletype signals and generate atext message that can be viewed over the display 52 of the terminal 50.

[0047] The process then proceeds to decision block 116 where the servicecenter waits another period of time to determine whether a response wasreceived from the vehicle 20 to the second message. If the vehiclesystem is operating in the TTY normal mode, the user may respond byentering text of a conversation through the keypad 54 in the portableTTY terminal 50. The modem 51 processes the information and generates aset of teletype signals reflective of the characters of the text messageentered by the user through the keypad 54. The teletype signals may bein the form of Baudot tones that are transmitted through the externalinterface 57 of the TTY terminal 50 and over the wire 45 in thecommunication cord 40.

[0048] The communication system 22 receives, through its interface 24,the set of teletype signals generated by the portable TTY terminal 50.The vehicle controller 36 and/or the transceiver 34 can be configured todetect the presence of the teletype signals generated by the portableTTY terminal 50. Thereafter, the transceiver 34 transmits messages overthe wireless communication link A. The messages may include the Baudottones themselves or generated messages that are representative ofinformation contained in the set of teletype signals received from theportable TTY terminal 50. For instance, in the later case of generatedmessages representative of the tones, the transceiver 34 may include anencoder that detects the presence of Baudot tones from the portable TTYterminal 50. After detection, the encoder may be configured to bufferthe incoming frames to detect the teletype character that the user isattempting to transmit. The encoder may then generate and transmit amessage over the wireless communication link A to the remote stationthat is representative of the information contained in the teletypesignals. The message may include a header, character information, thebaud rate, and any other processing information over the wirelesscommunication link A to the remote station. At the remote station, adecoder may be used to receive the message and regenerate the Baudottones corresponding to the character at the specified rate.

[0049] In process block 118, if the service center receives a responseto the second message, then the service center may proceed with thecommunication with teletype (TTY) messages and provide the operator ofthe vehicle 20 with the requested Telematics services. If there is noresponse to the second message, however, then the process may proceedwith further queries from the service center to the vehicle 20 or,alternatively, the process may end.

[0050] For incoming communications to the vehicle 20, the controller 36in the vehicle communication system 22 is configured to monitor thecellular transceiver 34 for pending incoming cellular communications.Upon receiving a pending communication, the controller 36 may beconfigured to notify the occupant of the vehicle 20 of a pendingcommunication via an audio or visual alert. The controller 36 will thendetermine whether the vehicle occupant will agree to accept thecommunication. In one embodiment, the controller 36 may make thisdetermination by waiting for a predetermined time period to detectwhether the occupant selects a button on the portable TTY terminal 50.If the pending incoming voice communication is not accepted, then thecontroller 36 can do nothing and let the communication transfer to anelectronic answering service. Alternatively, the controller 36 canrespond to the voice communication by sending a special TTY text messageto the incoming caller that the occupant of the vehicle is not able torespond to the call at this time.

[0051] If the controller 36 determines that the pending incoming voicecommunication is accepted, then the controller 36 may switch, transferor otherwise route the downlink communication to the portable TTYterminal 50 similar to the process described above after the vehicleoccupant has established a wireless communication link A.

[0052] The process described above may need to be modified depending onthe operational mode selected by the user. For instance, if the userdesires to operate the portable TTY terminal 50 in the normal TTY mode,then a set of teletype signals may be transferred from the portable TTYterminal 50 to the vehicle communication system 22 through the wire 45in the communication cord 40. The teletype signals in this case would begenerated by the modem 51 in the portable TTY terminal 50 after text isentered by the user through the keypad 54. Another set of teletypesignals may be transferred from the vehicle communication system 22 tothe portable TTY terminal 50 through the wire 47 in the communicationcord 40. The teletype signals in that case would be generated from thetransceiver 34 in the vehicle communication system 22 after messageswith teletype information are received over wireless communication linkA.

[0053] If, however, the user desires to operate the portable TTYterminal 50 in the VCO mode, the portable TTY terminal 50 may thentransmit the audio information received through the terminal'smicrophone 58 over the wire 45 in the communication cord 40.Alternatively, referring to FIGS. 4 and 5, a control message may be sentto the communication system 22 that instructs the system to connect theaudio information received through the vehicle's microphone 30 to thetransceiver 34 for conversations over wireless communication link A. Inthe VCO mode, the teletype signals received by the portable TTY terminal50 over the wire 47 in the communication cord 40 would still be capableof being viewed through the display 52.

[0054] If the user desires to operate the portable TTY terminal 50 inthe HCO mode, the portable TTY terminal 50 may then route the downlinkaudio information received from the communication system 22 to theterminal's speaker 56 over the wire 47 in the communication cord 40.Alternatively, a control message may be sent to the communication system22 that instructs the system to connect the downlink audio informationfrom the transceiver 34 to the vehicle's audio speakers 32. In the HCOmode, the teletype signals generated by the modem 51 would still be sentfrom the portable TTY terminal 50 to the vehicle communication system 22over the wire 45 in the communication cord 40.

[0055] One of the benefits of the present invention can be furtherillustrated with regard to the processes illustrated in FIGS. 7-10. Inparticular, FIGS. 7-10 illustrate processes in the vehicle controller 36based on the transfer of control information between the communicationcontrol unit 26 and the portable TTY terminal 50. As mentioned above,referring to FIG. 4, the portable TTY terminal 50 may be configured totransmit the control information in the form of Baudot tones from itsinternal modem 51 over wire 45 in the communication cord 40 to thevehicle modem 37. The vehicle modem 37 would then convert the tones to aformat type capable of being read and understood by the vehiclecontroller 36. In another embodiment, referring to FIG. 5, the portableTTY terminal 50 could transmit the control information in the form ofcontrol signals over control wire 43 in the communication cord 40.

[0056] Referring initially to FIG. 7, a flow diagram is illustrated thatshows one embodiment of a processing loop for communicating TTYinformation through the vehicle controller 36. In particular, at processblock 202, the vehicle controller 36 would send a command so that aprompt would be displayed at the portable TTY terminal 50. The vehiclecontroller 36 may then be configured to be idle or wait until one ofseveral events occurs. For instance, as shown in decision block 204, theprocess may proceed if the user enters information into the portable TTYterminal. Additionally, as shown in decision block 206, the process mayproceed if the vehicle controller 36 receives an incoming data message(such as an SMS message). Further, as shown in decision block 208, theprocess may proceed if the vehicle controller 36 receives an incomingcall over the wireless communication link A. Moreover, as shown indecision block 210, the process may proceed if the vehicle controller 36receives vehicle information that needs to be provided to the user ofthe vehicle 20.

[0057] Starting initially with decision block 204, the vehiclecontroller 36 may be configured to wait for commands or otherinformation provided by the user of the portable TTY terminal 50. Forexample, referring to decision block 212 in FIG. 8, the vehiclecontroller 36 determine whether the user desires to place a TTY call toa remote station. The system could be configured to place a TTY callafter the user enters certain characters such as “DIAL” and the ENTERkey on the keypad 54 of the portable TTY terminal 50. This would causethe portable TTY terminal 50 to send the information to the vehiclecommunication system 22. With regard to FIG. 4, the modem 37 in thevehicle communication system 22 would receive the appropriate TTY tonesfrom the portable TTY terminal 50. The modem 37 would then demodulatethe TTY tones and provide the “DIAL” command to the vehicle controller36. With regard to FIG. 5, the vehicle communication system 22 couldreceive the commands directly over a separate control wire 43.

[0058] If the user desires to place a TTY call, the process may thenproceed to decision block 214 where a determination is made whether atelephone number was included with the requested call. If a telephonenumber is provided, then the vehicle controller 36 will attempt to placea call to the desired telephone number as shown in process block 216. Ifthe telephone number is not provided, then the vehicle controller 36 mayattempt to place the call to a default telephone number associated witha remote station as shown in process block 218. Additionally, as shownin process block 220, the vehicle controller 36 may also send to theremote station any other information required for Telematicsapplications.

[0059] In either event, the process may continue as illustrated in FIG.10. FIG. 10 describes a process flow within the vehicle controller 36after a call has been established with a remote station. In particular,a call is established in process block 280 under one of the desiredoperation modes of the system (normal TTY mode, HCO mode, VCO mode).During a call, the process may enter into a loop that contains a varietyof decision blocks 282, 284, 286.

[0060] At decision block 282, a determination may be made whether thecall has ended. If the call has ended, the wireless communication link Abetween the vehicle communication system 22 and the remote station isterminated and the process returns back to block 202. If the call hasnot ended, the process may proceed to decision block 284.

[0061] At decision block 284, the vehicle controller 36 may make adetermination whether there has been any input by the user at theportable TTY terminal 50. If the user has provided no input, the processmay return to decision block 282. Otherwise, if user has provided input,the process may continue to decision block 286.

[0062] At decision block 286, the vehicle controller 36 may make adetermination whether the user desires to send the controller a command.This can be accomplished by searching for a character string such as“CMD” from the portable TTY terminal 50. If the user does not desire tosend the controller a command, then the process returns to decisionblock 282. Any characters entered by the user will be transmitted aspart of the call. If, however, the user does desire to send thecontroller a command during a call, then the process proceeds to block288 where the vehicle controller 36 will mute the TTY modems transmitaudio to the transceiver 34. Process will continue back to block 202where specific commands may be provided to the vehicle controller 36from the portable TTY terminal 50.

[0063] Referring back to FIG. 8, the vehicle controller 36 may befurther configured to allow the user to set the external interface tothe normal TTY mode, the VCO mode, or the HCO mode by entering thecharacters “TTY”, “HCO”, or “VCO” as shown in decision blocks 222, 224,226. The vehicle controller 36 may then configure the system to operatein one of the three modes as shown in process blocks 228, 230, 232 anddescribed in more detail above. After configuring the system to operatein one of the three modes, the vehicle controller 36 may send theappropriate information to the portable TTY terminal 50 so that it candisplay the mode of operation as illustrated in process blocks 234, 236,238. The process may then proceed back to process block 202.

[0064] Additionally, the vehicle controller 38 may be configured toallow the user to query the vehicle controller 36 regarding the currentmode of operation. For instance, the process may include a determinationwhether the user has entered the characters “MODE?” into the portableTTY terminal 50 as shown in decision block 240. In FIG. 9, if the userhas entered the characters “MODE?” into the portable TTY terminal 50,then the vehicle controller 36 would determine the mode of operation asillustrated in decision blocks 242, 244 and the results reported to theuser as performed in one of the reporting process blocks 234, 236, 238.

[0065] Alternatively, the portable TTY terminal 50 may be configured toissue the appropriate command strings such as those shown above whenappropriate buttons or switches (such as mode switch 64) are activated.

[0066] The vehicle controller 36 may be further configured to allow theuser to enter commands for the transmission of a data message. ShortMessage Service (SMS) is a type of data message used in cellular phones.As shown in decision block 246, the vehicle controller 36 may beconfigured to search for a string of characters such as “SMS” andtransmit any associated message. For instance, the user may enter “SMS888-555-1234 HI SALLY. DO YOU WANT TO MEET FOR COFFEE?”. The vehiclecontroller 36 in process 248 would then parse the command and send themessage (“HI SALLY. DO YOU WANT TO MEET FOR COFFEE?”) via SMS to theportable device associated with the number 888-555-1234. Referring backto decision block 206 and process block 270, any incoming data messagesreceived by the transceiver 34 could be sent to the portable TTYterminal 50. This would provide greater utility for the TTY terminaluser by greatly increasing the number of other people that they couldeasily communicate with. The process may then proceed back to processblock 202.

[0067] The vehicle controller 36 may be further configured to allow theuser to accept an incoming call. For instance, at decision block 252,the vehicle controller 36 would determine whether a blank input wasprovided at the portable TTY terminal 50. This could be created when auser depresses the ENTER key on the keypad 54. If a blank input wasprovided, the vehicle controller 36 may then determine whether anincoming call is present as shown in decision block 254. If there is noincoming call, the process may then proceed back to block 202.Otherwise, if an incoming call is present, the vehicle controller 36 maythen answer the incoming call as shown in process block 256.

[0068] The vehicle controller 36 may be further configured to allow theuser to return to a connection with a remote station that has beensuspended due to the user issuing the “CMD” command during the call.This command was described above with relation to process block 288 inFIG. 10. Here, at decision block 258, the vehicle controller 36 woulddetermine whether certain characters such as “RET” were provided at theportable TTY terminal 50. If the user has entered the characters “RET”,then the process continues to decision block 260 were a determination ismade whether an existing call exists with a remote station over wirelesscommunication link A. If so, the process continues back to the flowdiagram in FIG. 10, as described in more detail above. If not, then theprocess may continue back to process block 202.

[0069] The vehicle controller 36 may be further configured to allow theuser to end a call. In particular, at decision block 262, the vehiclecontroller 36 may make a determination whether the user has entered astring of characters such as “END”. In response to receive the command“END”, the vehicle controller 36 may then determine whether a call is inprogress as shown in decision block 264. If a call is in process, thevehicle controller 36 may end the call as shown in block 266. If a callis not in progress, the process may return back to block 202.

[0070] If the vehicle controller 36 does not understand any string ofcharacters or commands, the vehicle controller 36 may be configured tonotify the user that the inputted information was not understood. Inparticular, as shown in process block 268, if none of the commands wereunderstood, the vehicle controller 36 may send a response that isdisplayed on the portable TTY terminal 50 to indicate that the commandwas not understood by the vehicle controller 36.

[0071] Returning to decision block 204 in FIG. 7, if there is no userinput from the portable TTY terminal 50, then the process may proceed todecision block 206 where the vehicle controller 36 may make adetermination whether any incoming data messages have been received overthe wireless communication link A. If an incoming data message ispresent, then the process may proceed to block 270 where the vehiclecontroller 36 sends the data message (such as an SMS message) to theportable TTY terminal 50. The process may then continue back to block202. If there are no incoming data messages, then the process mayproceed to decision block 208.

[0072] At decision block 208, the vehicle controller 36 may make adetermination whether any incoming calls have been received over thewireless communication link A. If an incoming call is present, then theprocess may proceed to block 272 where the vehicle controller 36 sends amessage to the portable TTY terminal 50 notifying the user that anincoming call exists. The message may include any Caller ID associatedwith the incoming call. The process may then continue back to block 202and eventually to blocks 252, 254, 256 where the user may accept a call.If there are no incoming calls, then the process may proceed to decisionblock 210.

[0073] At decision block 210, the vehicle controller 36 may make adetermination whether any vehicle information needs to be communicatedto the user of the portable TTY terminal 50. For instance, the vehiclecontroller 36 may be connected to a vehicle's electronic control unit orvehicle's sensor bus. Any alerts or warnings received by the vehiclecontroller 36 may be communicated to the portable TTY terminal 50 inprocess block 274. The type of information may include alerts such asdoor ajar, low fuel, low oil, low tire pressure, headlights active, andso on. If there is no vehicle information to communicate to the user,then the process may proceed back to decision block 204.

[0074]FIGS. 11-12 illustrate another embodiment of a communicationsystem 22 in a vehicle 20 having the capability of transmitting andreceiving teletype information. In this embodiment, the externalinterface 24 embedded in the vehicle 20 may receive a first set ofteletype signals from a portable TTY terminal 50 through a TTY terminalaccessory 70. Additionally, the external interface 24 may send a secondset of teletype signals to the portable TTY terminal 50 through the TTYterminal accessory 70. For the purposes of illustration and description,an example of a TTY terminal accessory 70 in the form of a cellularphone will be used. However, the present invention is not limited tocellular phones and the TTY terminal accessory 70 could be any type ofadaptor box that allows for a serial communication link and havingspeaker and microphone functionality.

[0075] In this embodiment, the TTY terminal accessory 70 includes akeypad 72, a user input 74 with a mode switch, a controller 75, aspeaker 76, and a microphone 78. The TTY terminal accessory 70 may alsoinclude external interfaces 73, 77. As will be explained further below,in this embodiment, the operational mode switch is included in the TTYterminal accessory 70 through a user input 74. Depending on the desiredoperational mode, the TTY terminal accessory 70 will assist inswitching, transferring, or otherwise routing a communication to thecorrect destination.

[0076] The vehicle communication system 22 communicates with the TTYterminal accessory 70 through a communication cord 40 having a firstwire 45, a second wire 47, a ground wire 49, a control wire 43, and apower wire 41. The communication cord 40 has connectors 42 at each endthat plug into the interface 24 in the vehicle communication system 22and the interface 73 in the TTY terminal accessory 70. In turn, the TTYterminal accessory 70 may communicate with the portable TTY terminal 50through another communication cord 80 having a first wire 85, a secondwire 87, and a ground wire 89. The communication cord 80 has connectors82 at each end that plug into the interface 77 in the TTY terminalaccessory 70 and the interface 57 in the portable TTY terminal 50.

[0077] As will be explained below, one benefit of this design is that itallows a user to enter call information through keypad 72 whenestablishing a wireless communication link A. This may be of particularimportance to a vehicle communication system 22 that does not permitdirect entry of call information through an embedded keypad. Moreover,this design is important for a portable TTY terminal 50 that, itself,does not allow for the receipt or transfer of control informationthrough its external interface 57.

[0078] Another benefit of this design is that a user can take advantageof all three operational modes (normal TTY mode, VCO mode, and HCO mode)even though the portable TTY terminal 50 does not have a speaker ormicrophone. In particular, during the normal TTY mode, any text enteredinto the keypad 54 may be converted into a set of teletype signals bythe modem 51 and then transferred to interface 57 for communication tothe TTY terminal accessory 70 over the wire 85 in the communication cord80. The controller 75 in the TTY terminal accessory 70 would then ensurethat any teletype signals received through interface 77 from theportable TTY terminal 50 would be routed to interface 73. Accordingly,any teletype signals received from the portable TTY terminal 50 are sentto the vehicle communication system 22 over wire 45 in the communicationcord 40. The vehicle communication system 22 would then receive theteletype signals and then generate messages over the wirelesscommunication link A that contain the Baudot tones or other informationrepresentative of the tones. Additionally, the normal TTY mode wouldallow a user to read text of the conversation through the visual display52 of the portable TTY terminal 50. This may be accomplished by thecontroller 75 when teletype signals received from the vehiclecommunication system 22 over wire 47 in communication cord 40 aretransferred to the portable TTY terminal 50 over wire 87 incommunication cord 80. The teletype signals received by the portable TTYterminal 50 are converted to text by the modem 51.

[0079] On the other hand, during the VCO mode, the controller 75 maysend any audio information from microphone 78 to the vehiclecommunication system 22 over the wire 45 in the communication cord 40.Alternatively, in embodiments where the communication cord 40 allows thetransmission of control information, the VCO mode may allow a user toprovide audio information through the vehicle's microphone 30.Additionally, the VCO mode would allow a user to read text of theconversation through the visual display 52 of the portable TTY terminal50. This may be accomplished by the controller 75 when teletype signalsreceived from the vehicle communication system 22 over wire 47 incommunication cord 40 are transferred to the portable TTY terminal 50over wire 87 in communication cord 80. The teletype signals received bythe portable TTY terminal 50 are converted to text by the modem 51.

[0080] Furthermore, during the HCO mode, any audio informationtransmitted by the vehicle communication system 22, over the wire 47 inthe communication cord 40, may be heard through the speaker 76 in theTTY terminal accessory 70. Alternatively, in embodiments where thecommunication cord 40 allows the transmission of control information,the HCO mode may allow a user to receive audio information through thespeaker 32 embedded in the vehicle 20. Additionally, the HCO mode wouldallow a user to enter text of the conversation through the keypad 54 inthe portable TTY terminal 50. The text entered into the keypad 54 areconverted into a set of teletype signals by the modem 51 and thentransferred to interface 57 for communication to the TTY terminalaccessory 70 over the wire 85 in the communication cord 80. The teletypesignals received from the portable TTY terminal 50 are then sent to thevehicle communication system 22 over wire 45 in the communication cord40. The vehicle communication system 22 would then receive the teletypesignals and generate messages over the wireless communication link Athat contain the Baudot tones or other information representative of thetones.

[0081]FIGS. 13-14 illustrate another embodiment of a communicationsystem 22 in a vehicle 20 having the capability of transmitting andreceiving teletype information. In this embodiment, the externalinterface 24 embedded in the vehicle 20 may receive a first set ofteletype signals from the portable TTY terminal 50 and may further senda second set of teletype signals to the portable TTY terminal 50. Inthis embodiment, however, an operational mode switch 84 is embedded inthe vehicle 20 as part of the vehicle communication system 22. Dependingon the desired operational mode, the vehicle controller 36 will switch,transfer or otherwise route the communication to the correctdestinations.

[0082] In particular, the vehicle communication system 22 maycommunicate with the portable TTY terminal 50 through a communicationcord 40 having a first wire 45, a second wire 47, and a ground wire 49.The communication cord 40 has connectors 42 at each end that plug intothe external interface 24 in the vehicle communication system 22 and theexternal interface 57 in the portable TTY terminal 50.

[0083] Similar to the previous embodiment, one benefit of this design isthat a user can take advantage of all three operational modes (normalTTY mode, VCO mode, and HCO mode) even though the portable TTY terminal50 does not have a speaker or microphone. In particular, during thenormal TTY mode, any text entered into the keypad 54 may be convertedinto a set of teletype signals by the modem 51 and then transferred tointerface 57 for communication to the vehicle communication system 22over wire 45 in the communication cord 40. The vehicle communicationsystem 22 would then receive the teletype signals and then generatemessages over the wireless communication link A that contain the Baudottones or other information representative of the tones. Additionally,the normal TTY mode would allow a user to read text of the conversationthrough the visual display 52 of the portable TTY terminal 50. Thevehicle communication system 22 transmits teletype signals over wire 47in communication cord 40. The teletype signals received by the portableTTY terminal 50 are converted to text by the modem 51.

[0084] On the other hand, during the VCO mode, the vehicle controller 36may direct any audio information from the vehicle's embedded microphone30 to the transceiver 34 for transmission over the wirelesscommunication link A. Additionally, the VCO mode would allow a user toread text of the conversation through the visual display 52 of theportable TTY terminal 50. This may be accomplished by the vehicle'scontroller 36 when it directs teletype signals to the portable TTYterminal 50 over wire 47 in communication cord 40. The teletype signalsreceived by the portable TTY terminal 50 may then be converted to textby the modem 51.

[0085] Furthermore, during the HCO mode, the vehicle controller 36 maydirect that any audio information received by the transceiver 34, overwireless communication link A, be heard through the vehicle's embeddedspeakers 32. Additionally, the HCO mode would allow a user to enter textof the conversation through the keypad 54 in the portable TTY terminal50. The text entered into the keypad 54 are converted into a set ofteletype signals by the modem 51 and then transferred to interface 57for communication to the vehicle communication system 22 over wire 45 inthe communication cord 40. The vehicle communication system 22 wouldthen receive the teletype signals and generate messages over thewireless communication link A that contain the Baudot tones or otherinformation representative of the tones.

[0086]FIGS. 1-5, 11-14 illustrate embodiments where the externalinterface 24 is a hard-wired connection. FIGS. 15-16 illustrate anotherembodiment of a communication system 22 in a vehicle 20 where theexternal interface 24 is configured for a wireless connection B. Inparticular, the communication system 22 includes a short-rangetransceiver 92 and the portable TTY terminal 50 includes a short-rangetransceiver 94. This allows for a wireless connection B between thevehicle communication system 22 and the portable TTY terminal 50.Accordingly, the external interface 24 uses the wireless connection B toreceive a first set of signals from the portable TTY terminal 50 and tosend a second set of signals to the portable TTY terminal 50.

[0087] In one embodiment, the short-range transmitters 92, 94 may beenabled using Bluetooth™ technology. Bluetooth technology allows for thereplacement of a wired connection by enabling devices to communicatewith each other through a universal short-range radio link. A Bluetoothspecification is available on the Internet from the Bluetooth SpecialInterest Group (SIG) at www.bluetooth.com.

[0088] In a second embodiment, the short-range transmitters 92, 94 maybe enabled using 802.11. 802.11 is a family of specifications forwireless local area networks (WLAN) developed by a working group of theInstitute of Electrical and Electronics Engineers (IEEE). Alternatively,the short-range transmitters 92, 94 may be enabled using infraredcommunications under a protocol established by the Infrared DataAssociation (IrDA). The specification for one type of infraredcommunications is available on the Internet at www.irda.org.

[0089] The signals transferred between the vehicle communication system22 and the portable TTY terminal 50 may include the Baudot tones in anaudio format or may include digital messages that represent the Baudottones. If the Baudot tones are transferred, then the wirelesscommunication link B should be set to an audio format. For instance,using Bluetooth technology, the communication link may be set to theaudio profile to transfer the Baudot tones. The transfer of the Baudottones may require, however, a modem 37 in the vehicle communicationsystem 22. The modem 37 would enable the vehicle controller 36 tocommunicate with the portable TTY terminal 50, similar to that describedin relation to the embodiment in FIG. 4. If digital messages aretransferred, then the short-range transceivers 92, 94 may require acoder/decoder for generating digital messages and regenerating theBaudot tones at each side of the communication link.

[0090] In either event, during the normal TTY mode, any text enteredinto the keypad 54 may be transferred to short-range transceiver 94 fortransmittal over the wireless connection B. The vehicle communicationsystem 22 would then receive the text and generate messages over thewireless communication link A that contain the text. Additionally, thenormal TTY mode would allow a user to read text of the conversationthrough the visual display 52 of the portable TTY terminal 50. Throughthe vehicle's short-range transceiver 92, the vehicle communicationsystem 22 transmits signals over the wireless connection B to theportable TTY terminal 50. The signals received by the portable TTYterminal 50 are shown on visual display 52.

[0091] On the other hand, during the VCO mode, the controller 55 in theportable TTY terminal 50 may transfer any audio information from themicrophone 58, over the wireless connection B, to the transceiver 34 fortransmission over the wireless communication link A. Alternatively, thecontroller 55 in the portable TTY terminal 50 may send a control signalto the vehicle controller 36, over the wireless connection B, toinstruct the vehicle controller 36 to route any audio information fromthe vehicle's embedded microphone 30 to the transceiver 34 fortransmission over the wireless communication link A. Additionally, theVCO mode would allow a user to read text of the conversation through thevisual display 52 of the portable TTY terminal 50.

[0092] Furthermore, during the HCO mode, the controller 55 in theportable TTY terminal 50 direct any audio information received by thetransceiver 34, over wireless connection B, to the terminal's speaker56. Alternatively, the controller 55 in the portable TTY terminal 50 maytransmit a control signal to the vehicle controller 36, over thewireless connection B, to instruct the vehicle controller 36 to routeany downlink audio information received by the transceiver 34 to thevehicle's embedded speakers 32. Additionally, the HCO mode would allow auser to enter text of the conversation through the keypad 54 in theportable TTY terminal 50. The text entered into the keypad 54 areconverted signals by the controller 55 and then transferred to theshort-range transceiver 94 for communication to the vehiclecommunication system 22 over wireless connection B. The vehiclecommunication system 22 would then receive the signals and generatemessages over the wireless communication link A that contain the tonesor other information representative of the tones.

[0093] In a further embodiment, referring back to FIG. 3, the externalinterface 24 includes the vehicle microphone 30 and vehicle speakers 32.In that case, the teletype signals are transferred and received over theair to the portable TTY terminal 50 through sound waves. The portableTTY terminal 50 is configured to receive and send teletype signals fromthe vehicle microphone 30 and vehicle speakers 32. When receivingteletype signals from the vehicle speaker 32, the portable TTY terminal50 receives the teletype signals through its microphone 58 and then usesits modem 51 to translate the audible tones into a text format that candisplayed on display 52. When sending teletype signals to the vehiclemicrophone 30, the portable TTY terminal 50 takes text entered throughkeypad 54 and translates the text to audible tones that are then playedon the terminal speaker 56. The vehicle microphone 30 will then receivethe teletype signals and send them over the wireless communication linkA.

[0094] What has been described is a communication system in a vehiclethat includes the capability of transmitting and receiving teletypeinformation for physically impaired persons. The system and methodreduces the complexity and the number of distractions when answering orestablishing an external wireless communication with a remote station.The system and method also allows a user to use a variety of operationalmodes even if the portable TTY terminal does not contain a speaker ormicrophone. The system and method further reduces cost because thetransmission and reception of teletype information can be done withoutphysically embedding a teletype device in the vehicle. A physicallyimpaired person can use his or her own portable TTY terminal. The abovedescription of the present invention is intended to be exemplary onlyand is not intended to limit the scope of any patent issuing from thisapplication. The present invention is intended to be limited only by thescope and spirit of the following claims.

What is claimed is:
 1. A communication system in a vehicle, thecommunication system comprising: an external interface embedded in thevehicle for receiving a first set of teletype signals from a portableTTY terminal and for sending a second set of teletype signals to theportable TTY terminal; and a communication control unit embedded in thevehicle that is connected to the external interface, the communicationcontrol unit having a controller and a transceiver, the transceivercapable of transmitting messages over a wireless communication link thatcontain information from the first set of teletype signals, thetransceiver further capable of receiving messages over the wirelesscommunication link that contain information for the second set ofteletype signals.
 2. The communication system in claim 1, wherein theexternal interface is configured to receive a connector of a removablecommunication cord, the connector having first audio contact, a secondaudio contact, and a ground contact.
 3. The communication system inclaim 2, wherein the connector further has a control contact, thecontrol contact permitting the controller in the communication controlunit to at least receive control information from the portable TTYterminal or send control info to the portable TTY terminal.
 4. Thecommunication system in claim 2 further comprising a modem that isconnected between the controller in the communication control unit andthe external interface, the modem permitting the controller in thecommunication control unit to at least receive control information fromthe portable TTY terminal or send control information to the portableTTY terminal.
 5. The communication system in claim 1, wherein the TTYterminal has a mode switch, the mode switch allowing a user to operatethe TTY terminal in at least a normal teletype mode, a voice carry overmode, and a hearing carry over mode.
 6. The communication system inclaim 5 wherein the portable TTY terminal has at least a keypad and adisplay, the operation of the TTY terminal in the normal teletype modeallows the user to provide information for the first set of teletypesignals through the keypad of the portable TTY terminal and allows theuser to receive information from the second set of teletype signalsthrough the display of the portable TTY terminal.
 7. The communicationsystem in claim 5 wherein the portable TTY terminal has at least amicrophone and a display, the operation of the TTY terminal in the voicecarry over mode allows the user to provide audio information through themicrophone of the portable TTY terminal and allows the user to receiveinformation from the second set of teletype signals through the displayof the portable TTY terminal.
 8. The communication system in claim 5wherein the portable TTY terminal has at least a keypad and a speaker,the operation of the TTY terminal in the hearing carry over mode allowsthe user to provide information for the first set of teletype signalsthrough the keypad of the portable TTY terminal and allows the user toreceive audio information through the speaker of the portable TTYterminal.
 9. The communication system in claim 1 wherein the externalinterface may further receive the first set of teletype signals from aTTY terminal accessory and may further send the second set of teletypesignals to the TTY terminal accessory.
 10. The communication system inclaim 9 wherein the TTY terminal accessory is a portable cellular phone.11. The communication system in claim 9, wherein the TTY terminalaccessory has a mode switch, the mode switch allowing a user to operatethe communication system in at least a normal teletype mode, a voicecarry over mode, and a hearing carry over mode.
 12. The communicationsystem in claim 11 wherein the TTY terminal accessory is connectedbetween the communication system in the vehicle and the portable TTYterminal, the portable TTY terminal having at least a keypad and adisplay, the operation of the communication system in the normalteletype mode allows the user to provide information for the first setof teletype signals through the keypad of the portable TTY terminal andallows the user to receive information from the second set of teletypesignals through the display of the portable TTY terminal.
 13. Thecommunication system in claim 11 wherein the TTY terminal accessory isconnected between the communication system in the vehicle and theportable TTY terminal, the portable TTY terminal having at least adisplay, the TTY terminal accessory having at least a microphone, theoperation of the communication system in the voice carry over modeallows the user to provide audio information through the microphone ofthe TTY terminal accessory and allows the user to receive informationfrom the second set of teletype signals through the display of theportable TTY terminal.
 14. The communication system in claim 11 whereinthe TTY terminal accessory is connected between the communication systemin the vehicle and the portable TTY terminal, the portable TTY terminalhaving at least a keypad, the TTY terminal accessory having at least aspeaker, the operation of the communication system in the hearing carryover mode allows the user to provide information for the first set ofteletype signals through the keypad of the portable TTY terminal andallows the user to receive audio information through the speaker of theTTY terminal accessory.
 15. The communication system in claim 1 furthercomprising a mode switch that is embedded in the vehicle, the modeswitch allowing a user to operate the communication system in at least anormal teletype mode, a voice carry over mode, and a hearing carry overmode.
 16. The communication system in claim 15 wherein the portable TTYterminal has at least a keypad and a display, the operation of thecommunication system in the normal teletype mode allows the user toprovide information for the first set of teletype signals through thekeypad of the portable TTY terminal and allows the user to receiveinformation from the second set of teletype signals through the displayof the portable TTY terminal.
 17. The communication system in claim 15,wherein the communication system further comprising a microphoneembedded in the vehicle and the portable TTY terminal has at least adisplay, the operation of the communication system in the voice carryover mode allows the user to provide audio information through themicrophone of the communication system and allows the user to receiveinformation from the second set of teletype signals through the displayof the portable TTY terminal.
 18. The communication system in claim 15,wherein the communication system further comprises a speaker embedded inthe vehicle and the portable TTY terminal has at least a keypad, theoperation of the communication system in the hearing carry over modeallows the user to provide information for the first set of teletypesignals through the keypad of the portable TTY terminal and allows theuser to receive audio information through the speaker of thecommunication system.
 19. A communication system for a vehicle, thecommunication system comprising: a communication control unit embeddedin the vehicle; an external interface embedded in the vehicle, theexternal interface connected to the communication control unit; aremovable communication cord connected to the external interface; and aportable TTY terminal connected to the removable communication cord, theTTY terminal having a keypad and a display, the TTY terminal capable ofsending a first set of teletype signals and receiving a second set ofteletype signals; wherein the communication control unit is capable ofreceiving the first set of teletype signals from the portable TTYterminal over the removable communication cord and capable of sendingthe second set of teletype signals to the portable TTY terminal over theremovable communication cord.
 20. The communication system in claim 19,wherein the removable communication cord includes a first audio wire, asecond audio wire, and a ground wire.
 21. The communication system inclaim 20, wherein the removable communication cord further includes acontrol wire that permits the communication control unit embedded in thevehicle to at least receive control information from the portable TTYterminal or send control information to the portable TTY terminal. 22.The communication system in claim 20 further including a modem embeddedin the vehicle, wherein the modem permits the communication control unitembedded in the vehicle to at least receive control information from theportable TTY terminal or send control information to the portable TTYterminal.
 23. The communication system in claim 19, wherein the TTYterminal has a mode switch, the mode switch allowing a user to operatethe TTY terminal in at least a normal teletype mode, a voice carry overmode, and a hearing carry over mode.
 24. The communication system inclaim 23 wherein the operation of the TTY terminal in the normalteletype mode allows the user to provide information for the first setof teletype signals through the keypad of the portable TTY terminal andallows the user to receive information from the second set of teletypesignals through the display of the portable TTY terminal.
 25. Thecommunication system in claim 23 wherein the portable TTY terminalfurther includes a microphone, the operation of the TTY terminal in thevoice carry over mode allowing the user to provide audio informationthrough the microphone of the portable TTY terminal and allowing theuser to receive information from the second set of teletype signalsthrough the display of the portable TTY terminal.
 26. The communicationsystem in claim 23 wherein the portable TTY terminal further includes aspeaker, the operation of the TTY terminal in the hearing carry overmode allowing the user to provide information for the first set ofteletype signals through the keypad of the portable TTY terminal andallowing the user to receive audio information through the speaker ofthe portable TTY terminal.
 27. The communication system in claim 19further comprising a TTY terminal accessory, the TTY terminal accessoryconnected between the external interface embedded in the vehicle and theportable TTY terminal.
 28. The communication system in claim 27 whereinthe TTY terminal accessory is a portable cellular phone.
 29. Thecommunication system in claim 27, wherein the TTY terminal accessory hasa mode switch, the mode switch allowing a user to operate thecommunication system in at least a normal teletype mode, a voice carryover mode, and a hearing carry over mode.
 30. The communication systemin claim 29 wherein the operation of the communication system in thenormal teletype mode allows the user to provide information for thefirst set of teletype signals through the keypad of the portable TTYterminal and allows the user to receive information from the second setof teletype signals through the display of the portable TTY terminal.31. The communication system in claim 29 wherein the TTY terminalaccessory has at least a microphone, the operation of the communicationsystem in the voice carry over mode allows the user to provide audioinformation through the microphone of the TTY terminal accessory andallows the user to receive information from the second set of teletypesignals through the display of the portable TTY terminal.
 32. Thecommunication system in claim 29 wherein the TTY terminal accessory hasat least a speaker, the operation of the communication system in thehearing carry over mode allows the user to provide information for thefirst set of teletype signals through the keypad of the portable TTYterminal and allows the user to receive audio information through thespeaker of the TTY terminal accessory.
 33. The communication system inclaim 19 further comprising a mode switch that is embedded in thevehicle, the mode switch allowing a user to operate the communicationsystem in at least a normal teletype mode, a voice carry over mode, anda hearing carry over mode.
 34. The communication system in claim 33wherein the operation of the communication system in the normal teletypemode allows the user to provide information for the first set ofteletype signals through the keypad of the portable TTY terminal andallows the user to receive information from the second set of teletypesignals through the display of the portable TTY terminal.
 35. Thecommunication system in claim 33, wherein the communication systemfurther comprising a microphone embedded in the vehicle, the operationof the communication system in the voice carry over mode allows the userto provide audio information through the microphone of the communicationsystem and allows the user to receive information from the second set ofteletype signals through the display of the portable TTY terminal. 36.The communication system in claim 33, wherein the communication systemfurther comprises a speaker embedded in the vehicle, the operation ofthe communication system in the hearing carry over mode allows the userto provide information for the first set of teletype signals through thekeypad of the portable TTY terminal and allows the user to receive audioinformation through the speaker of the communication system.
 37. Amethod for establishing a wireless communication link between a vehicleand a remote station, the method comprising the steps of: determining,by the vehicle, whether an occupant of the vehicle desires to establisha wireless communication link with the remote station; establishing, bythe vehicle, the wireless communication link between the vehicle and theremote station after it is determined that an occupant desires toestablish the wireless communication link; transmitting, by the remotestation, a first message to the occupant of the vehicle, the firstmessage including a voice communication; waiting, by the remote station,for a response message from the occupant of the vehicle during a firstperiod of time, the response message including a voice communication;and if no response message is received from the occupant of the vehicleduring the first period of time, transmitting, by the remote station, asecond message to the occupant of the vehicle, the second messageincluding teletype information.
 38. The method in claim 37 wherein thestep of determining whether the occupant of the vehicle desires toestablish a wireless communication link with the remote station includesreceiving control information from a portable TTY terminal.
 39. Themethod in claim 37 further comprising the steps of: receiving, by thevehicle, the second message to the occupant of the vehicle; converting,by the vehicle, the teletype information in the second message to a setof teletype signals; and transmitting, by the vehicle, the set ofteletype signals to a portable TTY terminal.
 40. The method in claim 39further comprising the step of: waiting, by the remote station, for ateletype response message from the occupant of the vehicle during asecond period of time, the teletype response message including teletypeinformation.
 41. A method in a vehicle communication system forestablishing a wireless communication link between the vehiclecommunication system and a remote station, the method comprising thesteps of: sending a user prompt from the vehicle communication system toa portable TTY terminal; determining at the vehicle communication systemwhether a user input is received from the portable TTY terminal; if auser input is received from the portable TTY terminal, determiningwhether the user input includes a dial command; if the user inputincludes a dial command, establishing the wireless communication linkbetween the vehicle communication system and the remote station.
 42. Themethod in claim 41 further comprising the steps of: determining whetherthe dial command includes a telephone number; and if the dial commandincludes a telephone number, establishing the wireless communicationlink between the vehicle communication system and the remote stationbased on the telephone number included in the dial command.
 43. Themethod in claim 41 further comprising the steps of: determining at thevehicle communication system whether a second user input is receivedfrom the portable TTY terminal; if a second user input is received fromthe portable TTY terminal, determining whether the second user inputincludes an end call command; and if the second user input includes anend call command, terminating the wireless communication link betweenthe vehicle communication system and the remote station.
 44. The methodin claim 41 further comprising the steps of: determining at the vehiclecommunication system whether an incoming data message exists; and if anincoming data message exists, sending the incoming data message from thevehicle communication system to the portable TTY terminal.
 45. Themethod in claim 41 further comprising the steps of: determining at thevehicle communication system whether an incoming call exists; if anincoming call exists, sending a teletype message from the vehiclecommunication system to a portable TTY terminal notifying a user of theportable TTY terminal of the incoming call; determining at the vehiclecommunication system whether a second user input is received from theportable TTY terminal; if a second user input is received from theportable TTY terminal, determining whether the second user inputincludes an accept call command; and if the second user input includesan accept call command, establishing the wireless communication linkbetween the vehicle communication system and the remote station.
 46. Themethod in claim 41 further comprising the steps of: determining at thevehicle communication system whether a vehicle alert exists; and if avehicle alert exists, sending a teletype message from the vehiclecommunication system to the portable TTY terminal notifying a user ofthe portable TTY terminal of the vehicle alert.
 47. A method in avehicle communication system for establishing a wireless communicationlink between the vehicle communication system and a remote station, themethod comprising the steps of: determining at the vehicle communicationsystem whether an incoming call exists; if an incoming call exists,sending a teletype message from the vehicle communication system to aportable TTY terminal notifying a user of the portable TTY terminal ofthe incoming call; determining at the vehicle communication systemwhether a user input is received from the portable TTY terminal; if auser input is received from the portable TTY terminal, determiningwhether the user input includes an accept call command; and if the userinput includes an accept call command, establishing the wirelesscommunication link between the vehicle communication system and theremote station.
 48. The method in claim 47 further comprising the stepsof: determining at the vehicle communication system whether a seconduser input is received from the portable TTY terminal; if a second userinput is received from the portable TTY terminal, determining whetherthe second user input includes an end call command; and if the seconduser input includes an end call command, terminating the wirelesscommunication link between the vehicle communication system and theremote station.